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Constraining the equation of state in neutron-star cores via the long-ringdown signal
No full textMultimessenger signals from binary neutron star (BNS) mergers are promising tools to infer the properties of nuclear matter at densities inaccessible to laboratory experiments. Gravitational waves (GWs) from BNS merger remnants can constrain the neutron-star equation of state (EOS) complementing constraints from late inspiral, direct mass-radius measurements, and ab-initio calculations. We perform a series of general-relativistic simulations of BNS systems with EOSs constructed to comprehensively cover the high-density regime. We identify a tight correlation between the ratio of the energy and angular-momentum losses in the late-time portion of the post-merger signal, called the long ringdown, and the EOS at the highest pressures and densities in neutron-star cores. Applying this correlation to post-merger GW signals significantly reduces EOS uncertainty at densities several times the nuclear saturation density, where no direct constraints are currently available. Hence, the long ringdown can provide stringent constraints on material properties of neutron stars cores
When to Use Rectangular Waveforms in Dielectrophoresis Application to Increase Separation and Sorting Efficiency
No full textIn this study, the influence of using rectangular waveforms is comprehensively investigated on the separation and sorting efficiency of dielectrophoretic (DEP) processes. Besides positive effects on DEP experiments, cases of a diminished force due to rectangular waveforms are investigated and discussed. This investigation encompasses two primary experimental setups. First, microparticle‐focusing experiments are carried out using a pair of electrodes within a microfluidic channel. Second, separation experiments are performed using a macroscopic insulator‐based dielectrophoretic filter. The study reveals that harmonics of rectangular signals can have a positive impact on separation or sorting efficiency when compared to sinusoidal waveforms, provided that these harmonics contribute to the overall DEP force with the same sign. This positive effect is found to depend on the ratio between the applied fundamental frequency and the cross‐over frequency in the Clausius–Mossotti factor. However, violating related derived boundary conditions leads to negative effects and a decrease in the DEP net force
Enzymatic reaction network‐driven polymerization‐induced transient coacervation
No full textA living cell has a highly complex microenvironment whereas numerous enzyme‐driven processes are active at once. These procedures are incredibly accurate and efficient, although comparable control has not yet been established in vitro. Here, we design an enzymatic reaction network (ERN) that combines antagonistic and orthogonal enzymatic networks to produce adjustable dynamics of ATP‐fueled transient coacervation. Using horseradish peroxidase (HRP)‐mediated Biocatalytic Atom Transfer Radical Polymerization (BioATRP), we synthesized poly(dimethylaminoethyl methacrylate), which subsequently formed coacervates with ATP. We rationally explored enzymatic control over coacervation and dissolution, using orthogonal and antagonistic enzyme pairs viz., alkaline phosphatase, Creatine phosphokinase, hexokinase, esterase, and urease. ATP‐fuelled coacervates also demonstrate the enzymatic catalysis to prove its potential to be exploited as a cellular microreactor. Additionally, we developed ERN‐polymerization‐induced transient coacervation (ERN‐PIC), with complete control over the system, polymerization, coacervation, and dissolution. Notably, the coacervation process itself determines functional properties, as seen in selective cargo uptake. The strategy offers cutting‐edge biomimetic applications, and insights into cellular compartmentalization by bridging the gap between synthetic and biological systems. The development of temporally programmed coacervation is promising for the spatial arrangement of multienzyme cascades, and offers novel ideas on the architecture of artificial cells
Making BERT Feel at Home : Modelling Domestic Space in 19th-Century British and Irish Fiction
No full textWe introduce a novel approach to detecting domestic space in literary texts beyond explicit spatial markers like "home" or "house." Using a pre-trained English BERT model fine-tuned on manually annotated passages from a corpus of 19th-century British and Irish novels, we develop a method to operationalize and quantify domesticity in fiction. Our model captures the nuances of domestic space by analyzing contextual and relational cues rather than relying solely on toponymic and other explicit references. This approach offers new insights into the representation of space in literature, revealing the fluid and dynamic nature of domesticity in 19th-century British and Irish fiction
Architecture for sub-100 ms liquid crystal reconfigurable intelligent surface based on defected delay lines
No full textReconfigurable intelligent surfaces, comprised of passive tunable elements, are emerging as an essential device for upcoming millimeter wave and terahertz wireless systems. A fundamental aspect of the device involves the tuning technology used to achieve reconfigurability. Among alternatives such as semiconductors and micro-electromechanical systems, liquid crystal offers advantages including cost- and power-effective large-panel scalability. In this context, conventional liquid crystal-based reconfigurable intelligent surface approaches face limitations in optimizing for bandwidth, response time and loss simultaneously, requiring trade-offs between them. Here we detail an architecture for a liquid crystal-based reconfigurable intelligent surface with compact defected delay lines that provide continuous, 360-degree tunability, enabling fast response time, wide bandwidth and low loss. A reconfigurable intelligent surface with a thin 4.6 μm liquid crystal layer is designed, fabricated, and characterized, exhibiting response times of 72 milliseconds, insertion losses below 7 dB, and a 6.8 GHz (10.9%) bandwidth at 62 GHz, all while utilizing a lossy glass substrate and gold as a conductor
Unsicherheit in der Vibroakustik: Ein Überblick
No full textUnsicherheit ist allgegenwärtig und beeinflusst das Verständnis eines vibroakustischen Systems negativ. Auf der einen Seite führt Unsicherheit in der Modellbildung während der Entwurfsphase zur Streuung in der Vorhersage der vibroakustischen Eigenschaften des Systems. Auf der anderen Seite weicht die Systemdynamik während des Betriebs eines Systems aufgrund der unvollständigen Datenerfassung von der einer Prüfstandsmessung ab. Aufgrund steigender Anforderungen an die akustische Qualität von Produkten, z.B. akustikgerechte Gestaltung und Sound Design des Antriebstrangs einschließlich des Motorgeräuschs eines Fahrzeugs, soll ein besseres Verständnis der vibroakustischen Eigenschaften des Systems erreicht werden. Aus diesem Grund muss die zugrundeliegende Unsicherheit berücksichtigt werden. Unsicherheit kann beispielsweise durch probabilistische Methoden identifiziert und quantifiziert werden. Anhand der Betrachtung der Unsicherheit z.B. Wahrscheinlichkeitsverteilungen von vibroakustischen Zielgrößen kann das Systemverständnis verbessert werden. Weiterhin können zuverlässige Entscheidungen hinsichtlich der vibroakustischen Eigenschaften getroffen werden. Aufgrund dieses Potenzials wird die Betrachtung der Unsicherheit in der Vibroakustik im Rahmen dieses Beitrags vorgestellt. Dieser Beitrag fasst die wesentlichen Methoden und Begriffe zusammen und zeigt den Stand der Wissenschaft der Unsicherheit in der Vibroakustik auf
Vibroakustische Modellversuche
No full textJede physikalische Gleichung muss dimensionshomogen sein. Diese Aussage erscheint so selbstverständlich, dass sie kaum einer tiefergehenden Diskussion bedarf. Tatsächlich markiert sie den Ausgangspunkt der Ähnlichkeits- und Modelltheorie. In der Strömungsmechanik und Thermodynamik werden Verfahren zur Durchführung von ähnlichkeitsmechanischen Modellversuchen seit dem späten 19. und frühen 20. Jahrhundert entwickelt und eingesetzt, u. a. durch Hermann von Helmholtz [1, 2]. 1970 benennt Lothar Cremer die dimensionslose Wellenlänge Helmholtzzahl [3]. Im Themenfeld der Vibroakustik, d. h. der Entstehung, Ausbreitung und Abstrahlung von Körperschall, konnten sich Modellversuche bislang nicht durchsetzen. Zudem haben numerische Verfahren im Ingenieurwesen ähnlichkeitsmechanische Modellversuche ein Stück weit verdrängt. Andererseits sind Modellversuche hervorragend geeignet, um vibroakustische Eigenschaften maschinenbaulicher Systeme in frühen Entwurfsphasen abzusichern. Sie unterstützen somit schnellere, parallelisierte Produktentwicklungsprozesse.
Der vorliegende Beitrag ordnet zunächst die Begriffe Maschinenakustik, Modellversuche und Modelle ein. Anschließend werden die Grundlagen der Ähnlichkeitsmechanik erläutert. Die klassischen Ähnlichkeitsansätze werden sodann mit computergestützten Verfahren der Sensitivitätsanalyse kombiniert. Dies vereinfacht die Herleitung von Modellgesetzen an körperschallerregten Strukturen, da ausschließlich Ein- und Ausgangsgrößen wie beispielsweise Geometriedaten bzw. modale Größen oder Übertragungsfunktionen benötigt werden. Beispiele aus dem Maschinenbau zeigen, wie körperschallerregte Platten oder Getriebe skaliert werden können, welche Herausforderungen bei vibroakustischen Modellversuchen in der Praxis auftreten und wie sie beherrscht werden können. Schließlich sollen die Prinzipien der Modellähnlichkeit als Ausblick auf zukünftige Arbeiten im Hinblick auf Selbsthnlichkeit diskutiert und mögliche Anwendungsszenarien in der Vibroakustik aufgezeigt werden
Real-time indexing and visualization of LiDAR point clouds with arbitrary attributes using the M3NO data structure
No full textIn previous work, we have presented an approach to index 3D LiDAR point clouds in real time, i.e. while they are being recorded. We have further introduced a novel data structure called M3NO, which allows arbitrary attributes to be indexed directly during data acquisition. Based on this, we now present an integrated approach that supports not only real-time indexing but also visualization with attribute filtering. We specifically focus on large datasets from airborne and land-based mobile mapping systems. Compared to traditional indexing approaches running offline, the M3NO is created incrementally. This enables dynamic queries based on spatial extent and value ranges of arbitrary attributes. The points in the data structure are assigned to levels of detail (LOD), which can be used to create interactive visualizations. This is in contrast to other approaches, which focus on either spatial or attribute indexing, only support a limited set of attributes, or do not support real-time visualization. Using several publicly available large data sets, we evaluate the approach, assess quality and query performance, and compare it with existing state-of-the-art indexing solutions. The results show that our data structure is able to index 5.24 million points per second. This is more than most commercially available laser scanners can record and proves that low-latency visualization during the capturing process is possible
Differential cortical activation patterns: pioneering sub-classification of tinnitus with and without hyperacusis by combining audiometry, gamma oscillations, and hemodynamics
No full textThe ongoing controversies about the neural basis of tinnitus, whether linked with central neural gain or not, may hamper efforts to develop therapies. We asked to what extent measurable audiometric characteristics of tinnitus without (T) or with co-occurrence of hyperacusis (TH) are distinguishable on the level of cortical responses. To accomplish this, electroencephalography (EEG) and concurrent functional near-infrared spectroscopy (fNIRS) were measured while patients performed an attentionally demanding auditory discrimination task using stimuli within the individual tinnitus frequency (fTin) and a reference frequency (fRef). Resting-state-fMRI-based functional connectivity (rs-fMRI-bfc) in ascending auditory nuclei (AAN), the primary auditory cortex (AC-I), and four other regions relevant for directing attention or regulating distress in temporal, parietal, and prefrontal cortex was compiled and compared to EEG and concurrent fNIRS activity in the same brain areas. We observed no group differences in pure-tone audiometry (PTA) between 10 and 16 kHz. However, the PTA threshold around the tinnitus pitch was positively correlated with the self-rated tinnitus loudness and also correlated with distress in T-groups, while TH experienced their tinnitus loudness at minimal loudness levels already with maximal suffering scores. The T-group exhibited prolonged auditory brain stem (ABR) wave I latency and reduced ABR wave V amplitudes (indicating reduced neural synchrony in the brainstem), which were associated with lower rs-fMRI-bfc between AAN and the AC-I, as observed in previous studies. In T-subjects, these features were linked with elevated spontaneous and reduced evoked gamma oscillations and with reduced deoxygenated hemoglobin (deoxy-Hb) concentrations in response to stimulation with lower frequencies in temporal cortex (Brodmann area (BA) 41, 42, 22), implying less synchronous auditory responses during active auditory discrimination of reference frequencies. In contrast, in the TH-group gamma oscillations and hemodynamic responses in temporoparietal regions were reversed during active discrimination of tinnitus frequencies. Our findings suggest that T and TH differ in auditory discrimination and memory-dependent directed attention during active discrimination at either tinnitus or reference frequencies, offering a test paradigm that may allow for more precise sub-classification of tinnitus and future improved treatment approaches
Typical and extreme weather datasets for studying the resilience of buildings to climate change and heatwaves
No full textWe present unprecedented datasets of current and future projected weather files for building simulations in 15 major cities distributed across 10 climate zones worldwide. The datasets include ambient air temperature, relative humidity, atmospheric pressure, direct and diffuse solar irradiance, and wind speed at hourly resolution, which are essential climate elements needed to undertake building simulations. The datasets contain typical and extreme weather years in the EnergyPlus weather file (EPW) format and multiyear projections in comma-separated value (CSV) format for three periods: historical (2001–2020), future mid-term (2041–2060), and future long-term (2081–2100). The datasets were generated from projections of one regional climate model, which were bias-corrected using multiyear observational data for each city. The methodology used makes the datasets among the first to incorporate complex changes in the future climate for the frequency, duration, and magnitude of extreme temperatures. These datasets, created within the IEA EBC Annex 80 “Resilient Cooling for Buildings”, are ready to be used for different types of building adaptation and resilience studies to climate change and heatwaves